Treatment of unruptured arteriovenous malformations in the brain.

Clinical features and treatment results of 33 patients with unruptured arteriovenous malformations (AVMs) were evaluated. Nine AVMs were located in the frontal lobe, 8 in the motor cortex, 5 in the parietal lobe, 6 in the temporal lobe, 2 in the occipital lobe and 3 in other parts of the brain. Nine patients were treated with microsurgery and 24 with radiosurgery. Total extirpation of the AVM was performed in all 9 microsurgery patients. One patient with an AVM in the motor cortex experienced upper extremity weakness postoperatively. Eleven of 24 patients treated with radiosurgery had follow-up imaging studies. Obliteration was obtained in 8 patients and decreased size in 3. Complications included 1 patient with a hemiparesis and 1 with an AVM rupture prior to obliteration. The remaining 13 patients did not experience any complications over a mean period of 21.2 months. Microsurgery appears to be the best treatment for unruptured AVMs in non-eloquent areas. Radiosurgery is a safe, effective treatment for unruptured AVMs in eloquent areas, although a bleeding risk remains during the latency period prior to obliteration.